Eco-friendly vehicles such as hybrid vehicles and electric vehicles use a motor system configured of a motor and an inverter as their main power source. Therefore, torque and output performance of a driving motor considerably affect performance of such vehicles, and improvement and/or reduction in the output performance of the driving motor may affect overall performance of the vehicle.
To maintain stable driving performance of one such vehicle, it is important for the driving motor to constantly output a torque matching a required torque. Output performance of a permanent magnet synchronous motor is affected by operation conditions such as speed, voltage, and temperature. However, there is a need to consider the operation conditions, such as speed, voltage, and torque command, at the time of selecting a current command corresponding to the required torque in a current map. As such, when the temperature of the motor is not considered, a motor controller can select a current command for a reference temperature, and a torque error occurs due to a difference between the reference temperature and an actual temperature. Therefore, the driving motor may not constantly output a torque matching the required torque.